WASHINGTON – Wayne in Charlotte Hall has a question that’s frequently asked this time of year. He writes, “I expect my final mowing will be towards the end of October. Should I lower my tractor or mower for the final cut before winter sets in?”

Well, that’s kind of a trick question since you don’t reveal your current cutting height, Wayne. But, I’ll give you a direct answer.

Cool season grasses, the ones that stay green over winter, should be cut to three inches whenever they’re cut, no matter the time of year. Warm season grasses, the ones that go brown and dormant over the winter, are typically cut at right around two inches. Follow the rule for your type of grass.

You don’t want any turf to go into the winter scalped short. It could cause root damage, especially if we have a cold winter without snow cover. You also don’t want the grass to be too tall, as that can lead to snow mold after a wet winter.

In short, your cutting height should never change, no matter the season.

Grass does not like to grow under big trees

Scott in Frederick writes, “My small backyard gets a lot of shade because of a tree, which I like as it keeps the back of the house cool in the summer. Every spring I put down grass seed for shaded areas. The grass will grow, last about a month or so and then die off. Am I doing something wrong? Before the tree got large, I had plenty of grass. Maybe I have a grub issue. I just don’t know what to do.”

Sounds more like shade, root competition and bad timing on your part rather than grubs. Grass seed sown in spring almost always dies off by summer. You should be seeding in the very late summer. The ideal window is between Aug. 15 and Sept. 15. So if you want to try this season, get the seed down right away, while there’s still time for good root growth.

But, be aware that the competition for food and water from the roots of a big tree make it hard to keep any grass happy, especially in a small space. And even the most shade tolerant grass needs at least four hours of sun a day. If you don’t get that much, consider moving to a shade loving ground cover like pachysandra.

Banish brown patch and save the bay

Ernest in Spotsylvania writes, “Brown patch has ruined places in my lawn the last two years. How do I get rid of it? I’ve tried putting down fungus chemicals to no avail. Help! I’m all patched out.”

Well Ernie, chemicals won’t cure brown patch (circular areas of dead grass that typically appear during times of high temperatures and humidity), but they do cause it.

Brown patch is a classic result of over-feeding your lawn with cheap, quick- release chemical fertilizers.

To prevent the problem next season, switch to corn gluten meal or a bagged organic lawn fertilizer. And only feed your lawn twice, in the early spring and very late summer. Do not feed your lawn mid-summer, that equals brown patch problems.

Also, dethatch the lawn now if it needs it. And be sure to water infrequently in the future. No more than twice a week and only in the morning.

Bare minimum lawn care can prevent bare spots

Gail in Fairfax writes, “My husband prided himself on our front lawn for many years. But he passed away last October and bare patches have taken over a good portion of the lawn, as they have every summer. He said it was a fungus and treated it, but I always thought it was grubs. I found many while working in the flower garden and assumed they were in the lawn as well. Now, it’s fall and I never gave the lawn any food or weed treatments this year. What should I do to bring it back? I do have someone who cuts the lawn.”

Well, first, our condolences on your loss.

Now, your lawn needs a fall feeding. Get the person who cuts it to put some corn gluten meal or a bagged organic lawn fertilizer down as soon as possible. Make sure they don’t ever cut the lawn lower than three inches. Feed the lawn again early in the spring with corn gluten meal. And if you water, only water deeply but infrequently, no more than twice a week.

If the bare spots return, get back in touch and we’ll discuss your options, but I don’t think they will. This simple plan will deter both grubs and disease.

Looking for a bamboo lawyer?

We got a lot of reaction to our story last week about the legal precedent for property owners being responsible for invasive plants that cause damage to adjacent properties.

‘Phil’ in Derwood has a typical story. He writes, “My neighbor’s bamboo has crept under my fence and is breaking through my asphalt driveway. I’ve politely asked that they take care of the problem, but my polite requests have gone by the wayside. I hate the idea of a lawsuit, but since my neighbor doesn’t seem to care about destroying my property, I appear to be stuck with pursuing legal action. How do I proceed?”

The experts I consulted all agreed that you, and the many other listeners with next door bamboo problems, should contact a real estate lawyer who specializes in encroachment issues. It’s the same situation as if the neighbor had built a structure on your property, and the law is on your side.

Specifically, the law is a Supreme Court of Virginia ruling known as Fancher vs. Fagella, issued on September 14, 2007. It establishes a very strong precedent, and gives a great rundown on all the state laws that were considered in making the decision.

Oh, and virtually all the emails we received about encroaching plants were about running bamboo, one of the most rampant and potentially destructive plants in all of horticulture. So please don’t plant it without professional underground barriers if you live near anyone else. Or better yet, plant clumping bamboo instead, it’s just as attractive, but much better behaved.